Cardinal Timothy Dolan has penned an op-ed reacting to Donald Trump’s speech at his campaign launch for a 2016 presidential run–six weeks ago–calling the Republican candidate a harbinger of anti-Catholic, racist “nativism.”

During those happy days decades ago when I taught American religious history to university students, I spent a chunk of time in class on the ugly phenomenon called nativism, defined by the scholar and author Ray Allen Billington as, “organized, white, Protestant antagonism toward the Catholic immigrant.”

It flourished in our country during the 1840s and 1850s — actually becoming a popular political party, the Know-Nothings — and appeared again, in the 1870s, as the American Protective Association; in the 1920s, as the KKK; and during post-World War II America, as Protestants and Other Americans United for Separation of Church and State.

These nativists believed the immigrant to be dangerous, and that America was better off without them. All these poor degenerates did, according to the nativists, was to dilute the clean, virtuous, upright citizenry of God-fearing true Americans.

(Among other American minorities, it must be said, Catholics like me often drew the ire of nativists.)